Revitalizing the High School Curriculum in Biology

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Revitalizing the High School Curriculum in
Biology A Scientists Perspective (based on
a personal journey)
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The journey begins
Negative stereotypes of scientists
Drawn by teachers (!)
31 of horror movies have a mad, bad scientist.
11 have a scientist trying to do good.
Mad, bad and dangerous (Christopher Frayling)
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(No Transcript)
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BSCI 105 Principles of Biology Introduction to
Cells and Molecules
Anne Simon Fall 2006
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Syllabus for College Introduction to Biology

• Lecture Date Topic
  Reading
• 1 W 8/30 Overview and keys for success
  Chap 1
• 2 F 9/1 Basic chemistry- bonds, H20 and
  polarity Chap 2
• 3 W 9/6 Functional groups and
  macromolecules- Chap 5
• carbohydrates and
  lipids Chap 6, 103-113
• F 9/8 The structure and properties of
  proteins Chap 3, 46-62
• Special Topic The
  medical nightmare of misfolded proteins
• 5 M 9/11 The structure and properties of
  DNA/ RNA Chap 4, 74-85
• 6 W 9/13 Basic organization of cells
  Chap 7, 128-141
• Chap 8, 165-170
• 7 F 9/15 Membranes Chap 6, 113-126
  
• Chap 8, 138-144
• 8 M 9/18 Movement across membranes-
  diffusion, Chap 6, 118-124

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Syllabus for College Introduction to Biology
Lecture Date Topic
Reading 11 W 9/27 Enzymes,
equilibrium constants and free energy Chap 3,
62-70 12 F 9/29 Enzyme kinetics and
coupled reactions
Special Topic Cancer
chemotherapy- inactivating enzymes in nucleotide

biosynthesis 13 M 10/2
Introduction to metabolism Chap 9, 177-183
14 W 10/4
Metabolic pathways- glycolysis Chap
9, 183-186 15 F 10/6
Metabolic pathways- citric acid cycle
Chap 9, 186-190 16 M
10/9 Metabolic pathways- respiratory chain
Chap 9, 190-196
17 W 10/11 Fermentation Chap 9,
196-197 Special Topic The
making of regular, lite, and non-alcoholic beer
18 F 10/13 Control of
biochemical pathways Chap 9, 197-198
Special Topics Metabolic disorders
The Atkins
Diet- living on "no" carbohydrates 19 M
10/16 Photosynthesis Chap 10,
202-219
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Syllabus for College Introduction to Biology
Lecture Date Topic
Reading 20 F 10/20
Identifying DNA as the genetic material
Chap 14, 303-310 21
M 10/23 DNA Replication
Chap 14, 310-320 22 W 10/25
Transcription of DNA into RNA
Chap 15 Chap 16, 338-342 23
F 10/27 Control of gene expression-
prokaryotes Chap 17, 362-373
24 M 10/30 Control
of gene expression in eukaryotes Chap 18,
382-392 at the level of transcription 25
W 11/1 Control of gene expression
in eukaryotes (con't)
Special Topic Using reporter genes to
study gene expression (or making plants glow
in the dark) 26 F 11/3
Maturation of RNA Chap 16, 344-345 27
and 28 M 11/6 Translation and
effects of mutations Chap 16, 345-359 W 11/8
29 and 30 F 11/10 Genetic
engineering Chap 19, 401-420 M 11/13

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Syllabus for College Introduction to Biology

• Lecture Date Topic
  Reading
• 31 F 11/17 The cell cycle and
  how aberrations Chap 11, 227-245
• in
  the cell cycle lead to cancer
• Special Topic The
  involvement of p53 in cancer
• 32 M 11/20 Signal transduction Chap
  8, 170-174
• 33 W 11/22 Signal transduction
  
• 34 M 11/27 Animal development the
  early stages Chap 21, 449-460
• 35 W 11/29 The mechanisms of
  development
  
  
  
• 36 F 12/1 The mechanisms of
  development (cont)
• Special Topic
  Cloning animals
• Special
  Topic Stem cells
• 37 M 12/4 Introduction to animal and
  plant viruses Chap 34
• 38 W 12/6 Animal and plant viruses
  (cont)

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The problem
University of Maryland (and Massachusetts)
students who have taken (and passed) full year
courses in high school biology and chemistry
remember virtually nothing about cells and
molecules

• Students have no understanding of
• Basic chemistry Covalent polar/non polar
  bonds/hydrogen bonds
• The basic properties of atoms (e.g., charge on an
  electron)
• The basic properties of macromolecules (sugars,
  lipids, proteins)

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MCPS High School Science Biology Framework
(a very small section)

• 1. Describe the properties of water (polarity,
  density, cohesion, adhesion, and universal
  solvent).
• 2. Analyze the relationship between the
  properties of water and living systems.
• 3. Distinguish among the chemical formulas of
  carbohydrates, proteins, lipids and nucleic
  acids.
• 4. Describe the characteristics of carbohydrates
  (organic moleculemonosaccharides are building
  blocks, supplier of energy and dietary
  fiberstructural component of cells cell wall,
  cellulose, cell recognition).
• 5. Compare the use of carbohydrates and lipids
  as sources of energy.
• 6. Describe lipids (organic molecule, component
  of cell membranes, stored energy supply).
• 7. Describe the importance of lipids as a
  component of the lipid bi-layer in cellular
  membranes.
• 8. Investigate uses of lipids in living systems
  (hormones, steroids (cholesterol), wax.
• 9. Describe proteins (organic molecule, amino
  acids are building blocks, in structural and
  functional role, including enzymes).
• 10. Explain the role of proteins as a structural
  component of cells and their functions as
  catalysts in biochemical reactions (enzymes).
• Investigate how protein structure is subject to
  temperature and pH.
• Identify the monomers (building blocks) of
  lipids, proteins, carbohydrates, and nucleic
  acids. describe nucleic acids (organic molecule
  nucleotides are building blocks sugar,
  phosphate, nitrogen bases DNA is a double
  helix, RNA is a single strand DNA replication
  DNA role in storage of genetic information).
• 13. Identify the general role of minerals in
  living systems (calcium, iron, potassium, sodium
  and chloride).
• 14. Describe the role of vitamins in maintaining
  good health in the human body (vitamins C, K, D).
• 15. Correlate the process of osmosis with the
  size of a plant cell contractile vacuole.
• 16. Identify the effect of temperature on enzyme
  activity and metabolic rate.
• 17. Identify the effect of temperature upon the
  rate of diffusion and states of matter.

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Searching for the problems

• Since the biology assessment exams do not
  contain any questions on basic chemistry,
  teachers omitted the first few chapters of
  material.

• Worked with AP Biology students weekly Fall and
  Spring, 2005-2006
• Worked with Biology Faculty to enhance knowledge
  and teaching strategies
• Set up after school tutoring program in Fall
  2005 with UMd students

• 10th grade students had little discernable
  knowledge of biology from the classroom. All
  information was memorized with no context.

• AP biology students had poor conceptual
  understanding of all the material.

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Searching for the problems

• Teachers lacked a conceptual framework for
  teaching the material.
• Students had poor study skills.
• Students had poor test taking skills. Students,
  even those with knowledge of the subject, would
  guess at whatever answer "looked" correct and did
  not understand how to apply their knowledge to
  answer questions.
• Students had limited exposure to active learning
  techniques to better process and retain the
  material. Students just answering
  straightforward multiple choice questions were
  learning very little and retaining virtually
  nothing.

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Searching for the solutions
Teachers are the key

• How to refresh and improve the knowledge base of
  teachers-

• For current teachers
• Summer two-week biology institute (July
  24-August 4, 2006)
• (Funded by NSF)
• Four hours of material at the AP level
• Two hours of curriculum development

For new teachers Universities should require
all science teachers before they graduate to
TA the introductory course at the college
level (from the top current instructor)
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Problems with the curriculum
The current curriculum 1. Starts with several
weeks on simple laboratory techniques/measurement
Problem- no context 2. Very limited
time spent on basic chemistry Problem-
teachers were skipping the basic information that
students
absolutely require to make sense out
of the rest of the semesters
material 3.
Several weeks are devoted to vitamins before
studying enzymes Problem- how can students
understand the importance of vitamins without
the context of enzymes? 4.
Several weeks are devoted to enzymes (kinetics,
heat, pH) very early in the semester Problem-
too difficult too soon. No context. No
concurrent teaching of
biochemical pathways. Students still have no
understanding of what a protein
is (or what a chemical reaction is that enzymes
are catalyzing).
15
Searching for the solutions
The current curriculum 1. Starts with several
weeks on simple laboratory techniques/measurement
2. Very limited time spent on basic
chemistry Problem- teachers were skipping the
basic information that students
absolutely
require to make sense out of the rest of the
semesters
material 3. Several weeks are
devoted to vitamins before studying
enzymes Problem- how can students understand
the importance of vitamins without
the context of enzymes? 4. Several weeks
are devoted to enzymes (kinetics, heat, pH) very
early in the semester Problem- too difficult
too soon. No context. No concurrent teaching of
biochemical pathways. Students
still have no understanding of what
a protein is (or what a chemical reaction is
that enzymes are catalyzing).
Solution- combine with context. Learn
measurements with a defined scientific goal
16
Searching for the solutions
The current curriculum 1. Starts with several
weeks on simple laboratory techniques/measurement
2. Very limited time spent on basic
chemistry 3. Several weeks are devoted
to vitamins before studying enzymes Problem-
how can students understand the importance of
vitamins without the context of
enzymes? 4. Several weeks are devoted to
enzymes (kinetics, heat, pH) very early in the
semester Problem- too difficult too soon. No
context. No concurrent teaching of
biochemical pathways. Students still have no
understanding of what a protein
is (or what a chemical reaction is that enzymes
are catalyzing).
Solution- combine with context. Learn
measurements with a defined scientific goal
Solution- Interdisciplinary approach. Take the
time needed for students to understand molecules
Include exercises where students
learn to look at and write molecules
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Exercise 1 Writing molecules in shorthand
H
can be written
The hydrogens that follow a carbon (C) or oxygen
(O) or Nitrogen (N) in the shorthand version
are attached to that C or O or N Always write
the shorthand version of the molecule from left
to right
C
H
O H
CH3OH
H
H
H
H
C
H
C C H
can be written
CH3CH2CH3
H
H
H
H
H
H
The double bond must be between the carbons since
hydrogen can have only one bond
can be written
C
H
C C
CH3CH CH2
H
H
O
O
H
H
CH3 C CH3
can be written
H
C C
H
C
H
H
O
O
H
Notice that shorthand writing mainly affects
hydrogens, and carbons that are attached only
to hydrogens
can be written
H
C OH
C
C OH
CH3
H
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Exercise 1 Writing molecules in shorthand
B. Write out each bond on the following
shorthand molecules

• Write each of the following molecules in
  shorthand

H
H
H
CH3CH2CH2CH2CH2OH
H
C C OH
C
H
H
H
CH3
H
H
H
CH3CHCH3
H
H
C C
C
H
HOCH2CH3
O
H
H
H
C C
H
O
H
H
CH3 C CH2CH2OH
N H
H
C
H
CH3CH2CH C CH2
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Exercise 2 Assembling molecules
Using any combination of Carbon (C), Hydrogen
(H), Nitrogen (N) or Oxygen (O) atoms, create at
least 5 molecules using at least 8 atoms.
You can have any combination of the atoms (you
dont have to use each one) and any combination
of single, double and triple bonds. Dont
forget, carbon must have four bonds, nitrogen has
three bonds, oxygen has two bonds and hydrogen
has one bond. A double bond counts as two
bonds and a triple bond counts as three
bonds. Remember to use the new shorthand that
you have learned
Example
O
H
HO C N CH2OH
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Exercise 3 Are the molecules you assembled
polar or non-polar?
Look at each of the molecules you designed in
Exercise 2. Are these molecules polar (will
dissolve in water) or non-polar (wont
dissolve in water). The more polar bonds your
molecules have, the more polar the molecule that
you have created. Remember, polar bonds are ALL
bonds except for those that join carbon (C) and
hydrogen (H). So O-H, N-H, N-O, C-N are all
polar bonds. C-H and all bonds between identical
atoms (C-C, N-N, O-O) are non-polar bonds. If
your molecule has many polar bonds, but they are
all clustered on one side of the molecule, the
molecule could be non-polar and not dissolve
in water Example
O
This molecule is non-polar
HO C O CH2CH2CH2CH2CH2CH2CH2CH2CH3
Use the following information on real molecules
to help you decide if you have created polar or
non-polar molecules
Name
Polar or non-polar?
Methanol Polar
CH3OH
Ethanol Polar
(this is the alcohol in alcoholic beverages)
CH3CH2OH
Propanol Polar
(this is used to clean electronic equipment)
CH3CH2CH2OH
Butanol Non-polar
CH3CH2CH2CH2OH
Pentanol Non-polar
CH3CH2CH2CH2CH2OH
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Exercise 4 More advanced shorthand
Many molecules have lots of carbon-hydrogen bond.
To make it even simpler to write, every carbon
can be designated as a point. All bonds to
the point are shown. Since carbon always has 4
bonds, if bonds are missing, they are hydrogens
that are just not drawn
Write the shorthand for the following molecules
H
H
H
C
H
C
H
C
C
H
N
H
H
Can be written as
H
H
H
C
C
C
C
H
H
H
H
H
C
C
H
C
C
H
H
CH3CH2CH CH2
Can be written as
HO
O
O
CH3CH2CH2CH2CH2OH
C
C
C
H
H
Can be written as
Write out every atom for the following molecules
C
CH2CH3
H
C
N
N
H
H
ONLY carbons can be designated as points. All
other atoms (and any hydrogens attached to
them) must be shown.
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Exercise 5 Polar or non-polar?
Which of these real molecules are polar?
remember, polar molecules will have many polar
bonds scattered throughout the molecule Which
are non-polar? remember, non-polar molecules
will have MOSTLY non-polar bonds (C-H or C-C,
N-N, etc) (Write polar or non-polar
next to the molecule). Which is the MOST polar
molecule? the most polar molecule will be the
one with the highest ratio of polar to non-polar
bonds- It might not have any non-polar
bonds (Write most polar next to the
molecule) Which of these molecules are sugars
(equal number of carbons and oxygens and twice as
many hydrogens)? Write sugar next to
the sugar Which of these molecules are lipids?
(Remember, lipids are large, non-polar molecules)
(White lipid next to the lipids)
HC-OH HO- CH HO-
CH HC H2C-OH
H2C-OH HC-OH H2C-OH
H
H
O
O
When you eat butter or oil, this is what you are
eating
This is cholesterol. If your cholesterol
levels are too high, you have too much of
this molecule in your body
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Searching for the solutions
The current curriculum 1. Starts with several
weeks on simple laboratory techniques/measurement
2. Very limited time spent on basic
chemistry 3. Several weeks are devoted
to vitamins before studying enzymes Problem-
how can students understand the importance of
vitamins without the context of
enzymes? 4. Several weeks are devoted to
enzymes (kinetics, heat, pH) very early in the
semester Problem- too difficult too soon. No
context. No concurrent teaching of
biochemical pathways. Students still have no
understanding of what a protein
is (or what a chemical reaction is that enzymes
are catalyzing).
Solution- combine with context. Learn
measurements with a defined scientific goal
Solution- Interdisciplinary approach. Take the
time needed for students to understand molecules
Include exercises where students
learn to look at and write molecules
24
Searching for the solutions
The current curriculum 1. Starts with several
weeks on simple laboratory techniques/measurement
2. Very limited time spent on basic
chemistry 3. Several weeks are devoted
to vitamins before studying enzymes
4. Several weeks are devoted to enzymes
(kinetics, heat, pH) very early in the
semester Problem- too difficult too soon. No
context. No concurrent teaching of
biochemical pathways. Students still have no
understanding of what a protein
is (or what a chemical reaction is that enzymes
are catalyzing).
Solution- combine with context. Learn
measurements with a defined scientific goal
Solution- Interdisciplinary approach. Take the
time needed for students to understand molecules
Include exercises where students
learn to look at and write molecules
Solution- vitamins need to be introduced with
enzymes as co-factors
25
Searching for the solutions
The current curriculum 1. Starts with several
weeks on simple laboratory techniques/measurement
2. Very limited time spent on basic
chemistry 3. Several weeks are devoted
to vitamins before studying enzymes
4. Several weeks are devoted to enzymes
(kinetics, heat, pH) very early in the
semester
Solution- combine with context. Learn
measurements with a defined scientific goal
Solution- Interdisciplinary approach. Take the
time needed for students to understand molecules
Include exercises where students
learn to look at and write molecules
Solution- vitamins need to be introduced with
enzymes as co-factors
Solution- Introduce enzymes after cells, right
before the section on biochemical pathways
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Searching for the solutions
Biggest problem Its too much information
Its too much memorization
an enzyme is a biological catalyst

• Solution- simplify the basic subject curriculum
  in partnership with
• scientists who are experts in the material and in
  teaching the material

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Searching for the solutions

• Worked with AP Biology students weekly Fall and
  Spring, 2005-2006
• Worked with Biology Faculty to enhance knowledge
  and teaching strategies
• Set up after school tutoring program in Fall
  2005 with UMd students

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Factoids
Hybrid pony/zebra
1. Cloning
2. Hybrid animals
3. Chimeric animals

• Human-animal chimeras
• Pigs with human blood
• Mice with human brain cells
• Sheep with human livers and hearts
• Mice with human brainscoming soon

Hybrid lion/tiger
Chimeric goat/sheep
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Factoids
1. Cloning
2. Hybrid animals
3. Chimeric animals
4. Panspermia
Did life (bacteria) arrived on meteors 3.8
billion years ago?
Revived bacteria from amber (25 million years
old) Revived bacteria from salt deposits (250
million years old)
5. Influenza and the coming pandemic

• Science mistakes in popular movies/TV
• e.g., X-files baby who died of a lethal dominant
  genetic disorder

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In summary

• The state needs to vastly simplify the biology
  curriculum
• Teachers and administrators need to partner with
  scientists
• who are experts both in the material and in
  teaching the material
• Enhance teacher training in the material that
  they will be teaching
• Programs for current teachers/better training of
  new teachers
• Enhance the chemistry section of the biology
  curriculum
• Should all students have a semester of chemistry
  (with a biological
• theme) before taking biology? Do all classes
  need to be one year long?
• Sufficient time needs to be available to
  introduce students to exciting
• and thought provoking ideas and facts to
  emphasize the relevance of Biology
• Reduce the current emphasis on memorized
  unrelated facts